Objective: Little is known about the course of echocardiographic parameters used for the evaluation of valvular heart disease (VHD) during pregnancy, hampering interpretation of possible changes (physiological vs. pathophysiological). Therefore we studied the course of these parameters and ventricular function in pregnant women with aortic and pulmonary VHD. Methods: The cohort comprised 66 pregnant women enrolled in the prospective ZAHARA studies or evaluated by an identical protocol who had pulmonary VHD or aortic VHD (stenosis/prosthetic valve). The control group comprised 46 healthy pregnant women. Echocardiography was performed preconception, during pregnancy and 1 year postpartum. Peak gradient, mean gradient, aortic valve area (AVA)/effective orifice area (EOA), left ventricular ejection fraction (LVEF) and right ventricular function (RVF; TAPSE) were assessed. Results: Peak and mean gradients increased during pregnancy compared to preconception in women with aortic VHD and controls (p < 0.0125), but not in women with pulmonary VHD. AVA/EOA remained unchanged. Preconception and postpartum gradients were comparable in all groups. Mean LVEF was normal in pregnant women with VHD and controls. Mean TAPSE was lower (p < 0.001) in women with pulmonary VHD compared to women with aortic VHD and controls (<20 mm vs. ≥23 mm; p < 0.001). In women with pulmonary VHD a decrease of TAPSE was observed during pregnancy (p = 0.005). Conclusion: Physiological changes during pregnancy lead to increased Doppler gradients in women with aortic VHD. This increase was not found in women with pulmonary VHD, probably caused by impaired RVF. Therefore, evaluation of RVF during pregnancy might be important to prevent underestimation of the degree of stenosis.